Automatic release valve for air-brake systems



C. W. HURL.

AUTOMATIC RELEASE VALVE FOR AIR BRAKE SYSTEMS. APPLICATION FILED AUG.11, 1921.

1,406,020. Patented Feb. 7, 1922.

By I l Y 44"4 ATTORNEY.

UNITED STATES PATENTV OFFICE.

CHARLES W. EURL, 0F I\TA1\l"1YGLO, PENNSYLVANIA, ASSIGNOR T0 J. W. KPHART AND J. `W. LEECH, BOTH OF EBENSBURG BOROUGH, PENNSYLVANIA.

AUTOMATIC RELEASE VALVE FOR AIR-BRAKE SYSTEMS.A

Specification of Letters Patent.

Application filed August 11, 1921. Serial No. 491,441.

Nantyglo, in the county of Cambria and State of Pennsylvania, have invented certain new and useful Improvements in Automatic Release Valves for Air-Brake Systems, of which the following is a specification. y

This invention relates to the air brake systems of railway trains, and has for its principal object to provide a simply constructed attachment whereby the engineer will be able tohold the brakes of the forward cars applied while the brakes of the rear cars are being released.

Another object of the.` invention is to provide a device of Athis character which may be coupled into the ordinaryltrain pipe of the air brake system without structural change in the system and without interfering with; the ordinary voperations of the same.

Vith these and other objects in view, the invention consists in certain lnovel features of construction as hereinafter shown and described and then specifically pointed out in the claims, and in the drawings illustrative of the preferredembodiment of the invention:

Figure 1 is a side elevation of a portion of a conventional air brake system with the improved attachmentapplied.

Figure 2 is an enlarged sectional elevation of the improved attachment.

Figure 3 is a transverse section on the line 3-3 of Fig. 2.

Figure 4 is a detached bottom plan view of the piston head.

The improved device comprises a tubular body 10 having transverse diaphragme or partitions ,11 and 12 intermediate the ends and in spaced relation and a closure cap 13 in advance of the diaphragm 11. The portion of the body between the diaphragm 12 and its lower end is bored to receive a piston head 14 air tight, the latter having a stem or rod 15 extending through an opening in the diaphragm 12, and terminating .in a needle valve 16 adapted to engage a seat 16 in the diaphragm 11 when the rod 15 is elevated.

The rod 15 is threaded Where it passes Patented Feb. 7, 19,22;u y

through the piston 14 to receive'an adjust'- ing nut 18, to enable the piston to be ad? justed on the rod.

The rod 15 is likewise threaded in'ternie-k diate the ends as at 19 to receive adjusting nuts 20 to enable the positionof the rodfto beadjusted lrelative to the diaphragm 12 to control the action of the valve 16. y

yA spring 21 is disposed between the piston 14 and the diaphragm 12, and operates to hold the piston yieldably in itsy downward position and the valve 16 lnormally open.

formed in the body 10 between the diaphragms 11 and 12, to provide access to the interior of the body to enable the nuts 20 i to be adjusted. The opening23is provided with a detachablevclosure ,24 bolted or otherwise secured to the body@ and suitably packed to hold the pressure. y

The body 10 is designed tok be coupled to the train pipe of the air brakef's'ystem a f portion'of which is represented lat' 25, ,at

any convenient point, Vpreferably near the triple valve, represented conventionally at 26. The attachment may be connectedin any suitable manner, for instance by. a cionventional coupling 27, and will preferably be off-set from the train pipe. Y Y

A relatively small pipe 28'4isl connected to the exhaust 29 of the triple valve 26 and is turned over as shown at 30 and connected through the cap 13 as' shown in' Fig. 2;`

A portion of the brake cylinder is'rep'- resented at 31, the auxiliary reservoir 'at-32 and the. connection between the train pipe 25 and triple valve at 33, these parts being of the usual construction.

One set of the parts 31, 32 and 33 is attached to each car of the train in the usual manner, and one of the improved attachments associated with each of the triple valves.

When the engineer operates the valve in the locomotive cab to reduce the pressure in the train line inv the ordinary manner, to apply the-brakes, the pressure to the brake cylinder of the forward car or the one nearest the engine, is reduced first, consequently the brakes on the first car are applied first.

65 An exhaust pipe 22 is coupled'into the'k In the. improved device the springs 2l are Set to resist the. normal pressure in the train pipe, usually about 70 pounds to the square inch for freight trains to which the .improved deviceis more particularly applicable.V

With the improved device. applied to the y triple valve exhaust of'each car, the engineer, when the brakes are to be released, moves-the:controllingleverin his cab to full release position which action opens the wayl between the main supply reservoir on the looomotiveand. the `train linev the pressure inv which has been reduced about l0 pounds more or less, in applying the brakes. The pressure` in the train line. is thusr Vraised atithe. part nearest thelocomotive tonearly or quite' equal. tothe pressure in the supply tank,or. about 100 pounds and is gradually lessened towardv the rear of'the train. to

about;65, pounds.

The. high pressure fromthefstorage tank thus .iowsA to the train line and, increases the train line pressure at the front thereby causingvthe valves 16.l in this part of the train to', be closed and'shuttingoff jthe exhaustfrfom thetriple valves by holding the valves lclosedas far backin thetrain as theexcesspressure exceeds the` normal pressure .of .70.fpounds,but with the valvesl toward therear, or ythose subject to. a pressure .of 7 0:or less, open, and with the exhaust fromthetriple valvesvatthe rear also open. By this means the brakes at. the front are retained in applied positionso. long as. the pressurefinl the train pipe is abovel the normal, or 70.po.undslea.ving'the brake at the. rear free to be released, first, as the valves 16 at the rear remain open owing to,` the relatively low pressure, as Vbefore stated.'

Bythis simple arrangementy the engineer can easily controlthe. action, and cause the brakes ltoberele'ased -rfrom therear toward the frontof the train and effectuallyr preventfthe pilingau ofthe cars, vor the pullin of draw hea s, so liable to occur with the or i-nary arrangement when the engineer isvv careless or' inexperienced.

rear brakes will be` automatically releasedv Vsystems comprising a casing closed `at one end andv open at theother end andadaptedf to be coupled-at its .open end to thetrain pipe of the system, said` casinghaving Vtrans-y verse diaphragms in spacedV relationfintermediate the ends with a valve seat in one of the diaphragms, aV piston operating in the casing at its open end, a stem extending from the piston and'through the other diaphragm and terminating in a valveadaptedl to en.- Y

gage theseat, a spring operatingntovmain.- tain said pistonaty oneend V'of its stroke and the valve open, and a conductor element connecting with said casingand adapted to Y lbe coupled to the triple valveof the system.-V

2. Anautomatic release valve for air.- brake systems comprisinga casingradapted to be,

coupled between the train pipe andthe ex-k haust of the triplevalve,v said casing havingE an intermediate valve seat, a piston operatf ingy in the casing a stem-extending lfrom the piston and terminating in a valve adapts, ed to engage theseat, and a ,spring-operating to. maintain saidv piston-.in position to Y holdv the valve open.-

3. An automatic release valve for `airY brake systems comprising alcasingadapted to be coupled between the. trainA pipe and the ex-V haust of the triple valve, said casing having a valve seat, piston'foperatingvin the casing,

a stem extendingifrom the piston and terminating in a valve adapted to engage thek seat, and a spring Ioperating to maintainI said piston in positionato lhold `the valve, open.-

In testimony whereof, I 'ailix my signature hereto. f

CHARLES. Wlf HURL. 

